Automatic telephone system



v H. P. CLAUSEN.

AUTOMATIC TELEPHONE SYSTEM. 7

APPLICATION FILED DEC. 4- 1917.

Patnted May 25,192;

.y n H n i A J m /a I ha n 7 Q W m. H W

H. P. CLAUSEN.

AUTOMATIC TELEPHONE SYSTEM.

I I APPLICATION FILED DEC. 4. 1917- I 1,340,934, Patented May 25, 1920;

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HENRY 1?. GLAUSEN, OF MOUNT VERNGN, NEW YQRK, ASSIGNOR TO WESTERN ELECTRIC COMPANY, INCORPURATED, 0 1* NEN' YORK, "N. Y., A ,CORPORATION or new YORK.

AUTOIVIATIC TELEPHONE SYSTEM.

Specification of Letters Patent.

Patented May 25, teen.

Application filed December 4, 1917. Serial No. 205,336.

To (ZZZ whom it may concern:

Be it known that I, HENRY P. CLAusnN, a citizen or the United States, residing at Mount Vernom'in the county of VVestchester, State of New -fork, have invented certain new and useful improvements in Automatic Telephone Systems, of which the fol lowing is a tulhclear, concise, and exact de scri'ption.

T his invention relates to telephone exchange systems and more particularly to telephone systems employing machine switch ing.

One object of this inyention is to provide an improved arrangement whereby a calling line may be seized as a calledline while the calling subscriber has his receiver oil" the switchhook. Another object is the provision of improved means for immediately releasing a connection in case the called line" is busy. 7

in the operation of automatic telephone exchange systems a calling subscriber usually receives a busy tone in case the called line is found busy. Frequently there is considerable delay before the calling subscriber thorou; ily recognizes this busy signal and replaces his receiver upon the switehhook to render his line accessible as a calleil line.

A. feature oi this invention istheiprovision of means for producing the immediate release or": a connection between a calling line and a called line it the fcalled line is found busy. Another feature of this inven tion is the provision of means whereby acalling line is 'made selectable as it called line before the calling party hangs up his receiver in response to a busy tone.

It is thought that the invention will be best understood from the following descrip tion, reference being had to the accompany- 7 ing drawings which diagrammatically represent in Figs. 1 and 2 the circuits ol' an automatic telephone system for connectmg two subscribers lines together for conver sation.

When the subscriber at station A. re moves his receiver from the hook, a circuit is completed from grounded battery, contact 1, winding of relay 2, right-hand armature and contact oi relay 10, outer left-hand armature and back contact of plungermagnet 3, sender l, loop of substation A, inner left-hand armature and back contact of plunger magnet 33, letthand winding of busy tone apparatus 70 to ground. Relay 2 G11TJO1ZQS and completes a circuit from grounded battery, left-hand high resistance winding of plunger magnet 3, armature and contact of relay 2 to ground. Plunger magnet 3 becomes energized and attracts pluns ger 5 to extend the calling line to an idle selector switch] As soon as the contacts 6 and 7 are closed a circuit is completed from grounded battery, upper winding of relay 71, contact 8, upper armature and back contact of relay 9, contact 6, right winding of polarized relay 10, sender 4, loop ofsubstation A, contact '7, inner lower armature and back contact of relay 9, contact 11, lower winding of relay 71 to ground. The current flows over this circuitjust described in the wrong direction to cause the polarized relay to attract its armature at this time. Relay 71, however, becomes energized and completes a circuit from grounded battery, winding of slow release relay 12, armature and front contact of relay 71 to ground. Relay i2 completes a locking circuit for the plunger magnet 3 from grounded battery,

contact 1, right-hand low resistance wind ing of plunger magnet 3, contact 13, inner armature and front contact. of relay 12 to ground. This groundat the inner armature and front contact of relay i2 is also connected to terminal f -l", and multiples thereof to cause the calling line to test busy when tested as called line.

T he calling *ubscriber now operates his dial -l to cause a seriesot interruptions in line circuit. Jpon the iirst de e'nergizzn n oi 71, a circuit is compl l p d battery, winding of magwind .1g of slow release relay l3, armatu e and front contact of relay urc and bacl: contact of reture and bacr contact of 3 a play 19, armatur and back contact of relay lay 9. low

71 to ground. hi net 11' is energized and \Iif'SRC 'ES the l movement. Relay 18 i .loses a circuit from battery, windlng, of relay 20, ar-

:y 20 closes a loosing circuit sp fill."

g 1.. t 1 1, contact prunart' oilbrush shart' {not shown) one a and front contact of relay 18 to magnet 24;, ei'ma-ture 'aindvbiick; cohtleet of secondary magnet 2 1, primary ofi'rnorniel Contact 25, armat'ureland back cozitactfoi yea. lay E18, upperarmatureend front contact-hf e relay 0011152106 springs'21; brushQS, ita -Inina1j22 to g'rounchteinove the hrushee 26, 27' Y and; 28' into" engagement with the hextsefi of, terminalem This operati on' cominuesfhjntil all-idle trunk, is @ifound, at which time 'no ground Willi be found upon fche test terminal 32 thereof; VReIaY QO' then cle nergizegend (gompletes.mcircuit from grtjunded hattermf Winding; pf TeIaJy 'IEP, i hpperfar'mature end, .back 'contactl (if relay 20; Contact Spring-917 21;), lower armaqure nd beekcontzict ofrehjQQ primary o fi norfilell "c'ontact ifiifi, inner armfume and front'fco nta'ct of rel'ey l2 tolgrom id.

Relay 9 by e ttfactingyits{inner armetu esj dpehsrtheeifc uit of releyffl and also extends; the; 02111111 7 line: through to thebru'shes I :26] eley 7,1 deenergizesiand Opens the cireuit -ofrelay12,551 f fromgroiunded beta I e I I ground; Magnet- 4:1 1e fenergizedencl' mbves .3

the .b i ushesfl. 4:8, e9 'intef engagement 1'30 1,

f and 27.?

, eontact 03E rel 21 3 112 to ground; Megnet'fl is energized" l-I 1 responsento 'each'lnterruptlonf I substatlon A, contact 7, inner-lower armm Y Off the linecifcuit; but relays 12 111C118 are 3 so constructed that; they hold 'theii ennaa tt lres attracted duringthe short 'intefrup- I tions producecl' inftheir energizi rigicircuit during the sending of the impulses; Upon the completion; o fztheifirst 'seiieslof im ePUISBSf ELt WhiCh m thebrush sheft eh own') has"heen r movedy sd thet the brushes e 26; 27 and 28 are" in operative relation t withf the desired groupfoftrunks;lineireley fl v remains energized 01 a sufiiciehtlengthof e I gtimetoi cause the relay l8 todehergize; A

" e tery;winding ofisecondary n g-nep 24; an?

mature and back eccntees ofisecondary meg-m I Tihas time to jreoract 4 its armatures;

eircu it is thehieee hpleted from greu ncled befi 11131324; 'priinery'effnorfiml eont-atit 25', hima,

l 4 cure and back eontactiof reley 18 hpper armature endf rbn't ontact of relay 20,001, I I ta-ct springs '21, secondary ofl' noltmel centa' ct'. J v 22, primary off-normal Contact 23,,inne11 e'rmatuneend front conta'ct of felay lQ to ground. Thexenergizetiqn' of magnet 24 'inoves thebrushes 26, 27 a-fid '28 into' en-fjf' gagement Withthe firet set'o'f tei ln iealspf the selectedgroup dftru'nks. Ii the trunk cennectedflte, thisgsetof terminals isjbhs'yyj gi'ouhd will be found hponqthe' test 'telfmi- 11211 32 thereof, and the locking- 'c ireui tfo f re1ay20 WiHbecbmpltedjhtoughthe-brush 28,*term ine1 32 to this; ground. It will, be obseryed that I the "pfeviqusly" deserih'ed lockij Qing eireuifi of relay 20 is open at fcontect 11113011 the first I secendery step' of theiswitch. Since hthejjsecondary magfiet interrupts its .own energizing circuit by attracting its V z rmeture, it will immediately denefgize and I e egemi ,conlplete e *ac' reuliqv for, lt's elf fr m, grounded battery, 'Wmdmg; of I secondary of elay 9, centa'et hand .wiiiding o f relay 10, sender yloop 19f rectien be cause the "polaiiied' "relay 10' to a t tract-its armatureii Relejyp33, however, bef i comes energized m} clses a, circuit fmm grounded battery, winding of slow. releaee' re1ay136, armeturehndfrontcontactof re-f lay tmgrQund, -';Re1a y "36, byettracfingfi ite upper armature, fconneqtsfground to; the -3 3 8'0 iplunge fi-magnetBene giZed, this circuitle f' ingiclOsed befofre the, slow release rel terminal 32 to maintain the P relay ,9 and f g by eny ether selectdrgl switch. 7 3

; Thecsubscriber at substation All WTL PM; w'f l ates the Sender- 4 to,produceai secqnfl seriesf H of interruptions in the" line} circuit,- 'Thez firstj lihter ruptien causes the relay 33 -t0jde-- energize and close circuit from grounded Q Ybetteny, side-switch ztrm37' ih itrsfiret 150- 3, esitiolnsv Windifig; 0ffprimery;Jnegnet 31385 i Winchngfof slow fyelease" relay 39, 1'0Wei- L armatu e and heck 1eontagtfoffrelay 33 15 f B gfound. Megliet 38f is energizedf and ad T vances'the brush shaft (not show jone step I r in itsiprimaiymovement Be1ay-i39 elem e "fed battery, "Winding of :esc'apement magne 3 e "1 40,,armnm-9: andfrbnhcentact oi relay 39 v wee uad: 1 ene1 s e g z' ic ir e s spouse to 'eah interre ation efthe link'e izipthat'they hold;their1-firinat1ii7sQhfctfahaid armatuiefla nd fronbicontact of relay 36,]

energized" and closes a ,Tcircuit from gund- Sturee ridjfron teohtactof l eleyfi flbrush 27 ,1 terminal 31', contact 35", lower winding .qffre lay 33 to" ground. 1 nThe current flowing- 3 through thisjeircuitis still in the wrohg di- 3' Afteffthe impulses have been sent e t whichf 33 remains energized e suffieient'length; off

" time e to- :causeuthe" relay 397t deenergize.

Relay 39, by iret-re'cti g its ermature,f opens,

" fi-" i 5 3121 6 fwhiilhf'glenergizes' and yestthe side-switch @rmsf into" the'iri;

second, @Ositibng The subscriber ati ubste ermmreend back Contact; Of relay '33 $0 I timeithe,brilsh"shaftf?(not 'ehoyvii) ,hesbeen {11 ,-m OYCl: so {that the bi'ushes 4 8 49 and 50 are ,in operative relation with the gi qup of ftel J mihalsfc onteifiing thefcalled line, the relay circuit from; grounded ubifi lfy,IfSide-sWitehfi 3 arm t in j its 'sec ond,v pos'iti'en, secondary! megnet 4 1,1 upper armafiure andbeck contact of e ielay 42,, wjndingref relay 39,-lowerr f ,ev fmaturefjan'ti frent; cbntaefi qf relay 36,1

deenergizes and moves the side-switch arms into their third position. A circuit is now closed from grounded battery, winding of relay 47, armature and back contact of relay 40, side-switch arm 64 to ground. A circuit is also completed from grounded battery, side-switch 37 in its third position,

upper armature and back contact of relay 43, winding of relay 44, interrupter 45 to ground. Each time the interrupter closes this circuit, the relay 44 energizes and closes a circuit from ringing generator 46, lefthand armature and front contact of relay 44, upper armature and front contact of relay 47, brush 48, terminal 52, sender 51, ringer at substation B (not shown), terminal 53, brush 49, lower armature and front contact of relay right-hand armature and front contact of relay 44, to the ringing generator 46. Ringing current is thus intermittently applied to the called line.

As soon as the subscriber at substation B removes his receiver from the hook and the relay 44 is deenergized, a circuit is completed from grounded battery, upper winding of relay'55, left-hand armature and back contact of relay 44, upper armature and front contact of relay 4?, brush 48, terminal 52, sender 51, loop at substation B, terminal 53, brush 49, lower armature and front contact of relay 47, right-hand armature and back contact of relay 44,. lower winding of relay '55, to ground. Relay 55 becomes energized and completes a circuit from grounded battery, side-switch arm 37 in its third position, winding of relay 43, armature and front contact of relay 55, primary off-normal contact 56 to ground. Relay 43 becomes energized and by attracting its upper armature opens the circuit of the relay 44. Relay 43 by attracting its inner lower armature closes a locking cir-' cuit for itself from grounded battery, sideswitch arm 37 in its third position, winding of relay 43, inner lower armature of relay 43, primary oftnormal contact 56 to ground. The subscribers lines are now connected together for conversation.

lVhen disconnection is desired the sub scriber at substation A replaces his receiver upon its hook, relay 33 decnergizes and opens the circuit of relay 36. Relay 36 deenergizes and completes a circuit from grounded battery, winding of release magnet 57, primary oil-normal contact 58, lower armature and back contact of relay 36, armature and back contact of relay 33 to ground. Under the control of the release magnet 57, the connector switch is returned to its normal position. As soon as the relay 36 deenergizes it opens a circuit of relay 9 and plunger magnet 3. Relay 9 de energizes and completes a circuit from grounded battery, winding of release magnet 59, primary off-normal contact 60, lower armature and back contact of relay 12, lower armature and back contact of re lay 9, lower armature and back contact of relay 19, armature and back contact of relay 71 to ground. Under the control of release magnet 59, the first selector switch is returned to its normal position. The plunger magnet 3 deenergizes and returns the line switch to its normal position.

If the called line is busy, ground is found -'upon the test terminal 54 thereof, and therefore, when the relay 39 denergizes, after the third set of impulses, the magnet 40 is still held energized due to a circuit being closed from grounded battery, winding of magnet 40, contact 62, winding of relay 42, contact 63, side-switch arm 64, in its second position, brush 50, terminal 54 to ground' Relay 42 becomes energized and closes a locking circuit for itself from grounded bat:

tery, winding of magnet 40, contact 62,

winding of relay 42, inner lower armature and front contact of relay 42, primary oil'- normal contact 56 to ground. Relay 42 also closes a circuit from grounded battery, winding of relay 65, lower armature and front contact of relay 42 to ground. Relay by attracting its armatures reverses the connection of the battery to the calling line.

Current now flows in the proper direction through the right-hand winding of the polarized relay 10 to cause this relay to energize. Relay '10 closes a locking circuit for itself from grounded battery, armature and front contact of relay l0, left-hand.

winding of relay 10, right-hand armatureand front contact of relay 3 to ground. T he energization of relay 10 opens the circuit through the right-hand winding of the plunger magnet 3 so that the plunger 5 is released. Since the relay 10 is made slow to retract its armatures, it is still held energized, due to a circuit completed from grounded battery, armature and front con tact of relay l0, left-hand winding of relay 10, right-hand armature and back contact of plunger magnet 3, sender 4, loopcf sub station A, inner left-hand armature and back contact of plunger magnet 3, left-hand winding of busy tone apparatus 70 to ground. The busy tone is thereby connected to the calling line. The energization of relay 10 maintains the circuit of relay 2 open and thereby irevents the operation of j a lWllS As: soon as the callingv "subscriber, rafter thei h o The line; switch isv now in condition 1 to v,eX. tend the subscriberslline to anidle selector: switch when the subscriber again removes ,his receiver from the switchliook to initiate hearing the busy signalyreplaces. hisffre ceiveri on othe'switchhook, the circiutthrcugh I ah adwinding of reopened y causing this relay: to 'deenerglze.

a call. J

i f At the tinie'tl'iefplunger 5 wasreleas'ed byj the energization of relay l0,the,circuit of, relay 33was1vopened a mana e and'Z.--

j'This relay'j33 deenergized and caused the c release of the connector andthe firs t'sele'ctor switches in scribed- I e y 7 Let usgassume, that while the husysignal the same manner as above deis connectedtothe line leading ito station A g and before the subscriber thereat has re-g placed his receiver upon th'e switchhoohf "that a connector switch, whose brushes aredesignated SAS: and seizes the'termi- V nals 52, 53 and 5a of this particular line. Since the contact 18 is open at this time, no

ground will be found upon the test terminal 5%. The, side switch of the connector switch thereupon moves into its third position;

Since the subscriber at substation A hashis receiver oii' 'the hook, a circuit is closed from grounded battery, upon winding of a relay corresponding to relay 55, left-hand armature and back contactof a relay corresponding to relay 'l l, upper armature and frontcontact of a relay corresponding to relay 47, brush 4E8, terminal '52, right-hand winding of relay 10, sender 4, loop at substation A,

terminal 53', brush r9',-lower armature and front, contact of the relay corresponding to relay l7, r ght-hand armature and back contact of therelay corresponding to relay 44,

7 lower winding of relay 55 to ground. The I x I switches, means for operatlng' said relay to release said switches lfsald'called line 1s current flowing through this circuit is' in the direction to DGHtHLllZG the eflect of the current through the left-hand w ndingof relay 10. Therefore relay 1O deenergizes' and completesa circuit from grounded bat-c tery,contact 1, right-hand low resistance winding of plunger magnet 3, test terminal 54:,brush '50, through aside-switch arm corresponding to side -sw1tch arm 64 to ground. The current flowing through this low resistance winding of the plunger net 3 1s SllfilClGlll? to cause the magnet to,

energized and close a icircuitthrough the left-hand high resistance winding of plunger magnet 3 to attract the plunger 5;

jp'lishe e n 1 4 scribed, further {o signaling device to'said 'c allingline said called line isbu'sy.

'i with said calling line,

hangs up his receiver.

; in segmenta este m It ation' ma, now-conrerse, asoa' calle f the switchesu used in establishin this'l st telephonic. connection I is acconi ne'cessary;;, V a,

lt hat s'clainied isjz l V I L I 13 10 56"System, a alling=-- a called line, amen-numerical ls operating said relay-to connect; said busy 1111 a telel hone system,acallingflline,a

1111a,; p itclrasso ciatedgwitlr isaid: "calling; Tliney numerical switches, means for operatingfssaid switches toiestablish' connection between ing and called linesya-busy signaling device; polarized relay; associated with said-non numerical switch and-means rem-e e sing "the current through the polarized relay" for LY uie same': man er as" above de-1 o lescription -1Sydl118dM im- 7 calledline, a non-numerical switch associated said called line isbusy.

3. In a telephone system, a

switches to establish; a connection between said calling and said called lines,-a relay associated with said non-numerical switch arrangedjto control the release oiall said busy, and means. formaintaining said relay energized, to render said non-numericalswitch inoperative until the calling party 4c; In a telephone system, a callingline, a

numerical, switches, 1 l

calling line, a cal1ed;line,"a non-numerical ,switch asso-' ciated' with vsaid calling line, unumerical switches, means for operating all ofsaid' called line, a non-numerical switch 'a'ssoi- 'ciated with said calling line, numerical switches, means'ior operating all of said switches to establish a connection between said calling and said called lines, a relay associated with said non-numerical switch arranged to control the release of, all said switches, means for closing an operating circultfor said relay to release said switches if said called line is busy, and a locking circuit for said relay completed over said calling line to render said non-numerical switch in-' operativeuntil after the calling party hangs up his receiver. a V

5. In a telephone system, a calling line, a called line, means including a non-numerical switch individual to said calling line for establishing a connection between said calling and called lines, means for rendering said calling line non-selectable as a called line during the establishment of said connection, a busy signaling device, means for releasing said connection and for connecting said busy signaling device to said calling line if said called line is busy, and means controlled by said last mentioned means for rendering said calling line selectable as a called line before the calling party hangs up his receiver in response to said busy tone.

' 6. In a telephone system, a calling line, a called line, means including a nonnumerical switch associated with said calling line for establishing a connection between said calling and called lines, means for rendering said calling line non-selectable as a called line during the establishment of said connection, a relay associated with said nonnuinerical switch, a busy signaling device, means for closing an ope ating circuit for said relay if said called line is busy, means controlled by the operation of said relay for releasing said connection and for connecting said busy signaling device to said calling line, means controlled by the release or said non-numerical swltch for rendering said calling line selectable as a called line beiore said calling party hangs up his receiver in response to said busy signaling device, and

means operated if said calling line is selected as a called line before the calling party hangs up his receiver for disconnecting said busy signaling device from said calling lineand for maintaining said nonnumerical switch inoperative.

7. In a telephone systen1,a calling line, a called line, a non-numerical switch associated with said calling line, means for rendering said calling line non-selectable as a called line during the establishment of a connection, and means for rendering said line during the establishment of said connection, and means for rendering said call- 'ing line selectable as a called line before the calling party hangs up his receiver if said called line is busy.

9. In a telephone system, a calling line, a called line, a non-numerical switch associated with said calling line, numerical switches, means for operating all of said switches to establish a connection between said calling and said called line, a relay associated with said non-numerical switch arranged to control the release of all of said switches, and means for operating said relay to' release said switches if said called line is busy and for maintaining said relay energized to render said non-numerical switch inoperative until the calling party hangs up his receiver.

10. In a telephone system, a calling line, a called line, a non-numerical switch associated with said calling line, numerical switches, means for operating all of said switches to establish a connection between said calling and said called lines, means arranged to control the release of all 0t said switches, and means for operating said releasing means to release said switches it said called line isbusy and for rendering said calling line selectable asacalled line until said calling party hangs up his receiver.

In witness whereof, I hereunto subscribe igyi name this 27th day of November A. D.,

' HENRY 'P. OLAUSE'N. 

